Spirulina compounds show hypoglycemic activity and intestinal flora regulation in type 2 diabetes mellitus mice

Jingangteng capsules ameliorate liver lipid disorders in diabetic rats by regulating microflora imbalances, metabolic disorders, and farnesoid X receptor

BACKGROUND

The plant Smilax china L., also known as Jingangteng, is suspected of regulating glucose and lipid metabolism. Jingangteng capsules (JGTCs) are commonly used to treat gynecological inflammation in clinical practice. However, it is not clear whether JGTCs can regulate glucose and lipid metabolism, and the mechanism is unclear.

PURPOSE

To investigate the impact and mechanism of action of JGTCs on diabetes and liver lipid disorders in rats.

METHODS

The chemical constituents of JGTCs were examined using ultra-high-performance liquid chromatography with quadrupole time-of-flight mass spectrometry. A high-fat diet and streptozotocin-induced diabetes model was used to evaluate anti-diabetic effects by assessing blood glucose and lipid levels and liver function. The mechanism was explored using fecal 16S rRNA gene sequencing and metabolomics profiling, reverse transcription-quantiative polymerase chain reaction (RT-qPCR), and Western blot analysis.

RESULTS

Thirty-three components were identified in JGTCs. The serological and histomorphological assays revealed that JGTC treatment reduced levels of blood glucose and lipids, aspartate aminotransferase, alanine aminotransferase, and lipid accumulation in the liver of diabetic rats. According to 16S rDNA sequencing, JGTCs improved species richness and diversity in diabetic rats' intestinal flora and restored 22 dysregulated bacteria to control levels. Fecal metabolomics analysis showed that the altered fecal metabolites were rich in metabolites, such as histidine, taurine, low taurine, tryptophan, glycerophospholipid, and arginine. Serum metabolomics analysis indicated that serum metabolites were enriched in the metabolism of glycerophospholipids, fructose and mannose, galactose, linoleic acid, sphingolipids, histidine, valine, leucine and isoleucine biosynthesis, and tryptophan metabolism. Heatmaps revealed a strong correlation between metabolic parameters and gut microbial phylotypes. Molecular biology assays showed that JGTC treatment reversed the decreased expression of farnesoid X receptor (FXR) in the liver of diabetic rats and inhibited the expression of lipogenic genes (Srebp1c and FAS) as well as inflammation-related genes (interleukin (IL)-β, tumor necrosis factor (TNF)-α, and IL-6). Liver metabolomics analysis indicated that JGTC could significantly regulate a significant number of bile acid metabolites associated with FXR, such as glyco-beta-muricholic acid, glycocholic acid, tauro-beta-muricholic acid, and tauro-gamma-muricholic acid.

CONCLUSIONS

This was the first study to investigate the mechanisms of JGTCs' effects on liver lipid disorders in diabetic rats. JGTCs inhibited liver lipid accumulation and inflammatory responses in diabetic rats by affecting intestinal flora and metabolic disorders and regulating FXR-fat synthesis-related pathways to alleviate diabetic lipid disorders.

Study on the effect of licochalcone A on intestinal flora in type 2 diabetes mellitus mice based on 16S rRNA technology

Licorice, has a long history in China where it has various uses, including as a medicine, and is often widely consumed as a food ingredient. Licorice is rich in various active components, including polysaccharides, triterpenoids, alkaloids, and nucleosides, among which licochalcone A (LicA) is an active component with multiple physiological effects. Previous studies from our research group have shown that LicA can significantly improve glucose and lipid metabolism and related complications in Type 2 diabetes mellitus (T2DM) mice. However, research on the mechanism of LicA in T2DM mice based on intestinal flora has not been carried out in depth. Therefore, in this study, LicA was taken as the research object and the effects of LicA on glucose and lipid metabolism and intestinal flora in T2DM mice induced by streptozotocin (STZ)/high-fat feed (HFD) were explored. The results indicated that LicA could reduce serum TC, TG, and LDL-C levels, increase HDL-C levels, reduce blood glucose, and improve insulin resistance and glucose tolerance. LicA also alleviated pathological damage to the liver. The results also showed that LicA significantly affected the intestinal microbiota composition and increased the α diversity index. β Diversity analysis showed that after the intervention of LicA, the composition of intestinal flora was significantly different from that in the T2DM model group. Correlation analysis showed that the changes in glucose and lipid metabolism parameters in mice were significantly correlated with the relative abundance of Firmicutes, Bacteroidetes, Helicobacter, and Lachnospiraceae (p < 0.01). Analysis of key bacteria showed that LicA could significantly promote the growth of beneficial bacteria, such as Bifidobacterium, Turicibacter, Blautia, and Faecococcus, and inhibit the growth of harmful bacteria, such as Enterococcus, Dorea, and Arachnococcus. In conclusion, it was confirmed that LicA reversed the imbalanced intestinal flora, and increased the richness and diversity of the species in T2DM mice.

Effects of fermented feed of Pennisetum giganteum on growth performance, oxidative stress, immunity and gastrointestinal microflora of Boer goats under thermal stress

Introduction

This study was conducted to evaluate the effects of fermented feed of Pennisetum giganteum (P. giganteum) on growth performance, oxidative stress, immunity and gastrointestinal microflora of Boer goats under thermal stress.

Methods

The study was conducted during 45 days using twenty 2 months Boer goats. The goats were randomly allocated into two groups: NPG (n = 10; normal P. giganteum) and FPG (n = 10; fermented feed of P. giganteum), and the ratio of concentrates to roughage was 3:2. Both groups of animals were kept in sheds and exposed to summer thermal stress from 10:00 h to 18:00 h (temperature and humidity index, THI > 78). At the end of the study, the animals were slaughtered and assessed for various characteristics.

Results

The findings from the study revealed that FPG-feeding significantly increased (p < 0.05) average daily gain (ADG, 48.18 g) and carcass weight (4.38 kg), while decreased (p < 0.01) average daily feed intake (ADFI, 0.74 kg/d; p < 0.01) and the feed:gain (F/G, 15.36) ratio. The CAT, GSH-Px activities and GSH in serum, liver and spleen, and the levels of IgA, IgG, IgM, IL-2, IL-4 and IL-1β in serum of FPG-fed goats were significantly higher (p < 0.05) than those of NPG-feeding goats. Further, we found that FPG feed is rich in nutrients with Lactobacillus (65.83%) and Weissella (17.80%). Results for gastrointestinal microbiota composition showed that FPG-feeding significantly enhanced the abundance of Lactobacillus and unidentified Clostridiales, and reduced Anaerovibrio and Methanobrevibacter. Meanwhile, Spearman's correlation analysis showed that these microbiotas were closely related to the improvement of oxidative stress and immune indexes of goats.

Discussion

These results demonstrated that FPG-feeding not only reduces oxidative stress and improves ROS clearance to enhance antioxidant defense system, but also improves gastrointestinal microbiota to enhance immune function by overcoming the adverse effects of heat stress, and further improve growth performance of goats.

Probiotics-Fermented Grifola frondosa Total Active Components: Better Antioxidation and Microflora Regulation for Alleviating Alcoholic Liver Damage in Mice

Alcoholic liver damage is caused by long-term drinking, and it further develops into alcoholic liver diseases. In this study, we prepared a probiotic fermentation product of Grifola frondosa total active components (PFGF) by fermentation with Lactobacillus acidophilus, Lactobacillus rhamnosus, and Pediococcus acidilactici. After fermentation, the total sugar and protein content in the PFGF significantly decreased, while the lactic acid level and antioxidant activity of the PFGF increased. Afterward, we investigated the alleviating effect of PFGF on alcoholic liver injury in alcohol-fed mice. The results showed that the PFGF intervention reduced the necrosis of the liver cells, attenuated the inflammation of the liver and intestines, restored the liver function, increased the antioxidant factors of the liver, and maintained the cecum tissue barrier. Additionally, the results of the 16S rRNA sequencing analysis indicated that the PFGF intervention increased the relative abundance of beneficial bacteria, such as Lactobacillus, Ruminococcaceae, Parabacteroids, Parasutterella, and Alistipes, to attenuate intestinal inflammation. These results demonstrate that PFGF can potentially alleviate alcoholic liver damage by restoring the intestinal barrier and regulating the intestinal microflora.

Sanghuangporus vaninii fruit body polysaccharide alleviates hyperglycemia and hyperlipidemia via modulating intestinal microflora in type 2 diabetic mice

The disease of type 2 diabetes mellitus (T2DM) is principally induced by insufficient insulin secretion and insulin resistance. In the current study, Sanghuangporus vaninii fruit body polysaccharide (SVP) was prepared and structurally characterized. It was shown that the yield of SVP was 1.91%, and SVP mainly contains small molecular weight polysaccharides. Afterward, the hypoglycemic and hypolipidemic effects and the potential mechanism of SVP in T2DM mice were investigated. The results exhibited oral SVP could reverse the body weight loss, high levels of blood glucose, insulin resistance, hyperlipidemia, and inflammation in T2DM mice. Oral SVP increased fecal short-chain fatty acids (SCFAs) concentrations of T2DM mice. Additionally, 16S rRNA sequencing analysis illustrated that SVP can modulate the structure and function of intestinal microflora in T2DM mice, indicating as decreasing the levels of Firmicutes/Bacteroidetes, Flavonifractor, Odoribacter, and increasing the levels of Weissella, Alloprevotella, and Dubosiella. Additionally, the levels of predicted metabolic functions of Citrate cycle, GABAergic synapse, Insulin signaling pathway were increased, and those of Purine metabolism, Taurine and hypotaurine metabolism, and Starch and sucrose metabolism were decreased in intestinal microflora after SVP treatment. These findings demonstrate that SVP could potentially play hypoglycemic and hypolipidemic effects by regulating gut microflora and be a promising nutraceutical for ameliorating T2DM.